Summary proceedings from the cardiology group on postoperative cardiac dysfunction.

Department of Pediatrics, Stanford University School of Medicine, Division of Pediatric Cardiology, Stanford, California 94304, USA.

Abstract

As many as one third of the 35,000 to 40,000 infants born in the United States each year with significant congenital heart defects require surgery before the first year of life. Intraoperative support techniques, including cardiopulmonary bypass, can precipitate a complex, systemic inflammatory response that impairs the function of multiple organs and results in more hemodynamic instability and early morbidity in newborns than in older infants and children. Vasoactive agents are routinely used in the postoperative management of these patients either to treat or prevent hemodynamic instability and low cardiac output. However, the effectiveness of vasoactive agents used either individually or in combination in achieving specific therapeutic goals such as maintenance of a minimum cardiac index or arteriovenous oxygen saturation difference has not been systematically evaluated in preterm and term neonates. In addition, there are insufficient safety data for these agents in preterm and term neonates, both as individual agents and in combination. This article proposes a framework for developing prospective clinical studies to determine the efficacy of different vasoactive agents to promote adequate cardiac output and hemodynamic stability after neonatal cardiac surgery. The framework provides an overview of the issues relevant to the design of prospective clinical studies of vasoactive agents in the newborn patient population undergoing cardiac surgery. The issues identified by the cardiology group illustrate the difficulty of designing and executing clinical trials in vulnerable pediatric populations with limited numbers of patients, especially when standard practice is widely believed to be beneficial despite the lack of rigorous data to support such practice.